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Re: Multicast Routing Table Woes posted 04/15/2008
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Hi Guys,

Just to add a little to what you keep an eye out for Matt, "debug ip
pim" would be another resourceful debug to run when you are running
PIM. The FLAGS. I cannot over emphasize the importance of
understanding all the Flags. It always points you to a right direction
when troubleshooting an mrouting issue.

As for the mroute table:

(*, 225.0.0.1), 00:22:48/stopped, RP 15.15.15.15, flags: SJCLF
 Incoming interface: FastEthernet0/3, RPF nbr 3.3.3.1
 Outgoing interface list:
   FastEthernet0/2, Forward/Sparse, 00:19:41/00:03:16, H

This entry tells you this router knows about the Group (225.0.0.1). It
knows how to get to it (Incoming Interface, F0/3) and has someone
already joined this group downstream (Outgoing Interface List, F0/2).

(2.2.2.2, 225.0.0.1), 00:00:06/00:02:53, flags: LFT
 Incoming interface: FastEthernet0/1, RPF nbr 0.0.0.0, Registering
 Outgoing interface list:
   FastEthernet0/2, Forward/Sparse, 00:00:06/00:02:53, H

This entry tells you someone has already pushed traffic for the group.
And the mcast traffic is from 2.2.2.2, coming in through F0/1 and
going towards someone who is listening for the group, having joined
the group ealier, via F0/2.

Anyways, keep doing it over and over and over again, and it will all
makes sense eventually. One thing at a time.

HTH

Sadiq